One measurement of drilling quality is the finish provided to workpiece. Providing a high-quality finish on ductile materials, such as low carbon steel or alloy steel, can be particularly challenging, and improved finish is often a desired result.
U.S. Pat. No. 8,419,322 discloses tool for use in a preformed round hole. More precisely it discloses a cutting insert with a minor edge cutting flank adjoining a minor cutting edge against a direction of rotation, and comprising a support element arranged at a distance from the major cutting edge against a feed direction. The support element has a radius of revolution larger than a pitch circle radius of the cutting insert, during a drilling operation. The support element is mentioned as being able to provide both a supporting function and a smoothing function.
It is an object of the present application to provide a new and improved drill or drill head.